U.S. patent application number 13/593293 was filed with the patent office on 2013-03-07 for auto-injector for retractable prefilled syringe.
This patent application is currently assigned to UNITRACT SYRINGE PTY LTD. The applicant listed for this patent is Katlin M. Adlon, Joseph Hermes Kaal, Joel M. Ondrejickla, Christopher Charles Rafferty, Craig Stephen Thorley, Philip A. Weaver. Invention is credited to Katlin M. Adlon, Joseph Hermes Kaal, Joel M. Ondrejickla, Christopher Charles Rafferty, Craig Stephen Thorley, Philip A. Weaver.
Application Number | 20130060231 13/593293 |
Document ID | / |
Family ID | 46934669 |
Filed Date | 2013-03-07 |
United States Patent
Application |
20130060231 |
Kind Code |
A1 |
Adlon; Katlin M. ; et
al. |
March 7, 2013 |
AUTO-INJECTOR FOR RETRACTABLE PREFILLED SYRINGE
Abstract
An actuation mechanism for an automatic injector includes a
first actuation spring, a first actuation pill, a second actuation
spring, and a second actuation pill. In an initial configuration
the first actuation spring resides in a compressed, energized state
substantially within an upper portion of first actuation pill and
the second actuation spring resides in a compressed, energized
state between the first actuation pill and the second actuation
pill. An automatic injector includes a housing, an activation
mechanism, an actuation mechanism, and a syringe cartridge having a
plunger and a needle assembly. A retractable syringe may be
utilized as a syringe cartridge, such as a prefilled retractable
syringe with integrated safety features which retract the needle
after use. The automatic injector may be utilized to inject the
needle, deliver a drug treatment, and activate retraction of the
needle. Methods of assembly and operation are also provided.
Inventors: |
Adlon; Katlin M.;
(Harrisburg, PA) ; Weaver; Philip A.; (Denver,
PA) ; Kaal; Joseph Hermes; (Raworth, AU) ;
Rafferty; Christopher Charles; (Raworth, AU) ;
Thorley; Craig Stephen; (Largs, AU) ; Ondrejickla;
Joel M.; (Lewisberry, PA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Adlon; Katlin M.
Weaver; Philip A.
Kaal; Joseph Hermes
Rafferty; Christopher Charles
Thorley; Craig Stephen
Ondrejickla; Joel M. |
Harrisburg
Denver
Raworth
Raworth
Largs
Lewisberry |
PA
PA
PA |
US
US
AU
AU
AU
US |
|
|
Assignee: |
UNITRACT SYRINGE PTY LTD
Sydney
AU
|
Family ID: |
46934669 |
Appl. No.: |
13/593293 |
Filed: |
August 23, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
61526995 |
Aug 24, 2011 |
|
|
|
Current U.S.
Class: |
604/506 ;
137/15.01; 604/187; 604/228 |
Current CPC
Class: |
A61M 5/2033 20130101;
A61M 2005/3231 20130101; A61M 2005/2026 20130101; Y10T 137/0402
20150401; A61M 5/3234 20130101 |
Class at
Publication: |
604/506 ;
604/187; 604/228; 137/15.01 |
International
Class: |
A61M 5/315 20060101
A61M005/315; B23P 11/00 20060101 B23P011/00 |
Claims
1. An actuation mechanism for an automatic injector, said actuation
mechanism comprising: a first actuation spring, a first actuation
pill, a second actuation spring, and a second actuation pill,
wherein in an initial configuration the first actuation spring
resides in a compressed, energized state substantially within an
upper portion of first actuation pill and the second actuation
spring resides in a compressed, energized state between the first
actuation pill and the second actuation pill.
2. The actuation mechanism of claim 1, wherein the first actuation
pill and the second actuation pill are detachably connected by
engagement between one or more connector prongs of the first
actuation pill and one or more respective connection bridges of
second actuation pill.
3. The actuation mechanism of claim 2, wherein the one or more
connector prongs of the first actuation pill each have protrusions
which extend outwards from the first actuation pill.
4. The actuation mechanism of claim 1, wherein the first actuation
pill has one or more locking hooks at a proximal end of the first
actuation pill.
5. The actuation mechanism of claim 1, wherein the second actuation
pill has one or more retention prongs at a distal end of the second
actuation pill.
6. The actuation mechanism of claim 1, wherein the first actuation
pill has one or more guide prongs extending outwards from the first
actuation pill.
7. The actuation mechanism of claim 1, wherein the first actuation
pill and second actuation pill are substantially cylindrical.
8. An automatic injector comprising a housing, an activation
mechanism, an actuation mechanism, and a syringe cartridge having a
plunger and a needle assembly, wherein the actuation mechanism
comprises a first actuation spring, a first actuation pill, a
second actuation spring, and a second actuation pill, wherein in an
initial configuration the first actuation spring resides in a
compressed, energized state substantially within an upper portion
of first actuation pill and the second actuation spring resides in
a compressed, energized state between the first actuation pill and
the second actuation pill.
9. The automatic injector of claim 8, wherein the housing comprises
an upper housing and a lower housing, and wherein the upper
housing, the lower housing, the first actuation pill, and the
second actuation pill are substantially cylindrical.
10. The automatic injector of claim 8, wherein the first actuation
pill has one or more locking hooks at a proximal end of the first
actuation pill which initially engage a locking plateau at an
interior proximal end of the housing.
11. The automatic injector of claim 10, wherein the activation
mechanism is capable of engaging the one or more locking hooks of
the first actuation pill to disengage the locking hooks from the
locking plateau of the housing.
12. The automatic injector of claim 8, wherein the first actuation
pill and the second actuation pill reside within the housing and
are detachably connected with each other by engagement between one
or more connector prongs of the first actuation pill and one or
more respective connection bridges of second actuation pill.
13. The automatic injector of claim 12, wherein the one or more
connector prongs each have protrusions which interface with
longitudinal channels along an inner surface of the housing.
14. The automatic injector of claim 13 further comprising one or
more recesses on the inner surface of the housing, wherein, when
the protrusions of the connector prongs interface with the
recesses, the expansion of the protrusions into the recesses
permits the one or more connector prongs of the first actuation
pill to disengage from the one or more respective connection
bridges of second actuation pill.
15. The automatic injector of claim 8, wherein the syringe
cartridge is a retractable syringe that comprises a retractable
needle.
16. The automatic injector of claim 15, wherein the plunger is
capable of engaging the needle to facilitate retracting the
needle.
17. The automatic injector of claim 16, wherein retraction is
facilitated by a biasing member.
18. The automatic injector of claim 17, wherein the plunger
comprises the biasing member, wherein the biasing member is a
spring, a plunger inner, a plunger outer and one or more locking
members, the plunger inner and plunger outer co-operating to
releasably maintain said biasing member in an initially energized
state, and wherein the retractable needle comprises a cannula and a
needle body engageable by the plunger inner.
19. A method of assembling the automatic injector of claim 8, the
method comprising the steps of: compressing a second actuation
spring between a first actuation pill and a second actuation pill
and locking the second actuation spring in the compressed,
energized state by detachably engaging one or more connector prongs
of the first actuation pill with one or more respective connection
bridges of second actuation pill; (ii) inserting a first actuation
spring into a housing and compressing the first actuation spring
between the housing and the first actuation pill by detachably
engaging one or more locking hooks of the first actuation pill with
a locking plateau of the housing, wherein the first actuation
spring is initially maintained in a compressed, energized state
substantially within an upper portion of the first actuation pill;
and (iii) inserting a syringe cartridge comprising a plunger and a
needle assembly into the housing such that a proximal end of the
plunger contacts the second actuation pill.
20. The method of claim 19 further comprising the step of:
attaching an activation mechanism to the housing, wherein the
activation mechanism is configured to contact the one or more
locking hooks of the first actuation pill upon activation.
21. A method of operating the automatic injector of claim 8, the
method comprising the steps of: (i) disengaging one or more locking
hooks of a first actuation pill from a locking plateau of a
housing, wherein such disengagement permits a first actuation
spring to expand substantially along a longitudinal axis of the
housing from its initial energized state; (ii) disengaging one or
more connector prongs of the first actuation pill from
corresponding connection bridges of a second actuation pill,
wherein such disengagement permits a second actuation spring to
expand substantially along the longitudinal axis of the housing
from its initial energized state; and (iii) activating a retraction
mechanism of a syringe cartridge comprising a plunger and a needle
assembly, wherein the needle assembly comprises a retractable
needle having a cannula and a needle body, to retract the
retractable needle.
22. The method of claim 21 further comprising the steps of:
operating the plunger of the automatic injector to deliver a
substance to a recipient.
23. The method of claim 21 further comprising, prior to step (i),
the step of: unlocking an activation mechanism and activating the
activation mechanism.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to U.S. Provisional
Application No. 61/526,995, filed on Aug. 24, 2011, which is
included by reference herein in its entirety for all purposes.
FIELD
[0002] THIS INVENTION relates to automatic injectors for
retractable syringes. More particularly, this invention relates to
actuation mechanisms for automatic injectors, automatic injectors
for retractable syringes, the methods of operating such devices,
and the methods of assembling such devices.
BACKGROUND
[0003] Manually activated syringes are commercially available from
a variety of manufacturers, including the owner and assignee of the
present invention, and are used in the administration of drug
solutions, drug suspensions, vaccines, medicinal therapies, and any
other liquid medicament by parenteral injection. Such syringes are
commonly utilized by medical practitioners to administer injections
to patients but are difficult to use by self-administering
patients.
[0004] An auto-injector is an automatic injection device designed
to facilitate delivery of a dose of medicament to a patient through
a hypodermic needle, the injection usually being administered by
the patient themselves. An auto-injector works, for example, by
delivering an injection automatically upon activation by the
patient. This is in contrast to a conventional manually activated
syringe where the patient themselves needs to directly depress a
plunger into a barrel containing medicament in order to effect the
injection. Auto-injectors have proven particularly useful in
allowing the medically untrained user to administer a parenteral
injection, and can provide both psychological and physical
advantages to patients. Patients needing to inject medication for
chronic disease management have used auto-injectors since the first
reusable auto injector was introduced in the 1990s. An auto
injector provides protection for the primary container, generally a
pre-filled syringe, and offers an easy-to-use solution for
automatic injection of medication. As used herein, the terms
"automatic injector" and "auto-injector" are meant to refer to the
same devices.
[0005] In addition to automatic needle insertion and dose delivery,
some auto-injectors also incorporate safety mechanisms to
automatically protect the patient from the needle after use. The
automatic injectors of the prior art are usually provided with
needle shields which extend over the needle when actuated. However,
such safety mechanisms may fail to actuate and/or can be easily
reversed, thereby leaving the patient exposed to the needle and
susceptible to injury. Additionally, known automatic injectors
generally link visual, tactile or audible indicators to the end of
plunger stroke or actuation of some safety mechanism, instead of to
the end of drug dose. Accordingly, the self-administering patient
is not provided with an indication that the drug has been fully
delivered and may remove the needle or actuate the safety
mechanisms prematurely.
SUMMARY
[0006] The present invention provides actuation mechanisms for
automatic injectors, automatic injectors for retractable syringes,
the methods of operating such devices, and the methods of
assembling such devices. The automatic injectors of the present
invention provide integrated safety features which automatically
retract the needle or cannula into the device to, for example,
prevent injuries related to accidental needlestick. Additionally,
the embodiments of the present invention provide true end of dose
indication to users, informing the user that the drug delivery has
completed and that the device is safe for removal and disposal.
Accordingly, the novel devices of the present invention alleviate
one or more of the problems associated with prior art devices, such
as those referred to above.
[0007] In a first embodiment, the present invention provides an
actuation mechanism for an automatic injector. The actuation
mechanism includes a first actuation spring, a first actuation
pill, a second actuation spring, and a second actuation pill,
wherein in an initial configuration the first actuation spring
resides in a compressed, energized state substantially within an
upper portion of first actuation pill and the second actuation
spring resides in a compressed, energized state between the first
actuation pill and the second actuation pill. The first actuation
pill and the second actuation pill are detachably connected by
engagement between one or more connector prongs of the first
actuation pill and one or more respective connection bridges of
second actuation pill. The one or more connector prongs of the
first actuation pill may each have protrusions which extend
outwards from the first actuation pill.
[0008] The first actuation pill may have one or more locking hooks
at a proximal end of the first actuation pill. Similarly, the
second actuation pill may have one or more retention prongs at a
distal end of the second actuation pill. Furthermore, the first
actuation pill may have one or more guide prongs extending outwards
from the first actuation pill. The first actuation pill and second
actuation pill are substantially cylindrical and may be made of a
number of standard materials, preferably the same or different
plastics.
[0009] In another embodiment, the present invention provides an
automatic injector having a housing, an activation mechanism, an
actuation mechanism, and a syringe cartridge having a plunger and a
needle assembly. The actuation mechanism may be as described above
and have a first actuation spring, a first actuation pill, a second
actuation spring, and a second actuation pill, wherein in an
initial configuration the first actuation spring resides in a
compressed, energized state substantially within an upper portion
of first actuation pill and the second actuation spring resides in
a compressed, energized state between the first actuation pill and
the second actuation pill. The housing may be a single component or
may comprise two or more components such as, for example, an upper
housing and a lower housing. The upper housing, the lower housing,
the first actuation pill, and the second actuation pill may be a
myriad of shapes, but are preferably substantially cylindrical.
[0010] In at least one embodiment of the present invention, the
first actuation pill has one or more locking hooks at a proximal
end of the first actuation pill which initially engage a locking
plateau at an interior proximal end of the housing. The activation
mechanism is capable of engaging the one or more locking hooks of
the first actuation pill to disengage the locking hooks from the
locking plateau of the housing upon activation by the user. The
activation mechanism may include one or more locking grooves within
which corresponding locking prongs of the housing may travel. In
one configuration of the activation mechanism, the locking prongs
may prevent activation of the activation mechanism. In another
configuration of the activation mechanism, however, such as by
rotation of the activation mechanism for example, the locking
prongs may permit the activation of the activation mechanism.
[0011] In a preferred embodiment, the first actuation pill and the
second actuation pill reside within the housing and are detachably
connected with each other by engagement between one or more
connector prongs of the first actuation pill and one or more
respective connection bridges of second actuation pill. The one or
more connector prongs may each have protrusions which interface
with longitudinal channels along an inner surface of the housing.
One or more recesses may exist on the inner surface of the housing,
wherein, when the protrusions of the connector prongs interface
with the recesses, the expansion of the protrusions into the
recesses permits the one or more connector prongs of the first
actuation pill to disengage from the one or more respective
connection bridges of second actuation pill. According, by user
action on the activation mechanism, the activation mechanism
engages the one or more locking hooks of the first actuation pill
to disengage the locking hooks from the locking plateau of the
housing. This action permits the first actuation spring to expand,
thereby translating the actuation mechanism within the housing in
the distal direction along the axis of the automatic injector. As
the protrusions reach recesses within the inner surface of the
housing, the one or more connector prongs of the first actuation
pill are permitted to disengage from the one or more respective
connection bridges of second actuation pill. This action permits
the second actuation spring to expand, thereby translating the
second actuation pill in the distal direction along the axis of the
automatic injector. If the syringe cartridge contains a drug
treatment, such as in the case of a pre-filled syringe, the
function of the actuation mechanism may be utilized to inject a
needle and deliver the drug treatment into a patient. Optionally,
when a retractable syringe is utilized as a syringe cartridge, the
actuation mechanism may further be utilized to activate a
retraction mechanism.
[0012] In a preferred embodiment of the present invention, the
syringe cartridge of the automatic injector is a retractable
syringe. Such syringes may further contain safety features which
retract the needle after use, providing desirable needle-stick
prevention, and prevent re-use of the syringe. Suitably, the
plunger is slidably moveable within the barrel of the syringe to
thereby facilitate delivery of the drug treatment to a user,
patient or other recipient. The retractable syringe may include a
retractable needle assembly. Preferably, the plunger is capable of
engaging the needle assembly, or a portion thereof, to retract the
cannula or needle. Suitably, retraction of the needle is
facilitated by a biasing member such as a spring, elastic or other
member capable of storing and releasing energy to facilitate needle
retraction. It will be appreciated that the retractable syringe may
comprise any needle retraction mechanism that is operable with the
automatic injector disclosed herein. By way of example, the needle
retraction mechanism may be as described in International
Publication WO2006/119570, International Publication WO2006/108243,
International Publication WO2009/003234 and International
Publication WO2011/075760, although without limitation thereto.
[0013] According to one embodiment, the retractable syringe
comprises: a plunger comprising a biasing member, a plunger inner,
a plunger outer and one or more locking members, wherein the
plunger inner and plunger outer co-operate to releasably maintain
said biasing member in an initially energized state; and a needle
assembly comprising the retractable needle, wherein the retractable
needle comprises a cannula and a needle body engageable by the
plunger inner. Preferably, a plunger seal is mounted to the plunger
inner and is capable of engaging said needle body. Preferably, the
needle assembly may further comprise a needle seal that retains the
retractable needle, wherein the cannula of the retractable needle
passes through the needle seal to permit delivery of the mixed
substances or mixture to a user, patient, or other recipient.
[0014] In at least one embodiment, the syringe further comprises a
release ring. Suitably, the release ring is at a proximal end of
the syringe barrel and is engageably or connectably coupled,
connectable or affixed to the barrel. The release ring may be a
separate component or integral with the barrel. The release ring
may activate needle retraction after the plunger inner of the
retractable syringe has engaged the needle body.
[0015] Upon activation of needle retraction, the plunger inner and
plunger outer disengage allowing the biasing member to expand from
its initially energized state. The plunger outer remains
substantially in contact or connection with the release ring, while
the plunger inner is axially translated in the proximal direction
by release of the biasing member to enable retraction of the
cannula and needle body.
[0016] Suitably, the retractable syringe comprises one or more
plunger locking systems. In one embodiment of said locking system,
the plunger inner of the plunger comprises a locking member which
is capable of engaging the release ring of the syringe after needle
retraction to thereby prevent or impede further movement of the
plunger inner relative to the release ring. In at least one
embodiment of the present invention, the retractable syringe
comprises a retraction mechanism essentially as described in
WO2011/075760. Additionally or alternatively, the force of the
second actuation spring acting upon the plunger outer itself may
prevent or "lock-out" the plunger outer from axial travel in the
proximal direction after actuation.
[0017] In a further embodiment, the present invention provides a
method of assembling an automatic injector which includes the steps
of: (i) compressing a second actuation spring between a first
actuation pill and a second actuation pill and locking the second
actuation spring in the compressed, energized state by detachably
engaging one or more connector prongs of the first actuation pill
with one or more respective connection bridges of second actuation
pill; (ii) inserting a first actuation spring into a housing and
compressing the first actuation spring between the housing and the
first actuation pill by detachably engaging one or more locking
hooks of the first actuation pill with a locking plateau of the
housing, wherein the first actuation spring is initially maintained
in a compressed, energized state substantially within an upper
portion of the first actuation pill; and (iii) inserting a syringe
cartridge comprising a plunger and a needle assembly into the
housing such that a distal end of the plunger contacts the second
actuation pill. The method may further comprise the step of:
attaching an activation mechanism to the housing, wherein the
activation mechanism is configured to contact the one or more
locking hooks of the first actuation pill upon activation.
[0018] In a further embodiment, the present invention provides a
method of operating an automatic injector which includes the steps
of: (i) disengaging one or more locking hooks of a first actuation
pill from a locking plateau of a housing, wherein such
disengagement permits a first actuation spring to expand
substantially along a longitudinal axis of the housing from its
initial energized state; (ii) disengaging one or more connector
prongs of the first actuation pill from corresponding connection
bridges of a second actuation pill, wherein such disengagement
permits a second actuation spring to expand substantially along the
longitudinal axis of the housing from its initial energized state;
and (iii) activating a retraction mechanism of a syringe cartridge
comprising a plunger and a needle assembly, wherein the needle
assembly comprises a retractable needle having a cannula and a
needle body, to retract the retractable needle. The method may
further include the steps of: operating the plunger of the
automatic injector to deliver a substance to a recipient. Prior to
step (i), the method may further include the step of: unlocking an
activation mechanism and activating the activation mechanism.
[0019] Throughout this specification, unless otherwise indicated,
"comprise," "comprises," and "comprising" are used inclusively
rather than exclusively, so that a stated integer or group of
integers may include one or more other non-stated integers or
groups of integers.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Non-limiting embodiments of the invention are described
herein with reference to the following drawings wherein:
[0021] FIG. 1A shows an isometric view of an automatic injector,
according to one embodiment of the present invention;
[0022] FIG. 1B shows an isometric view of the interior components
of the automatic injector shown in FIG. 1a;
[0023] FIG. 2 shows an exploded view of an automatic injector,
according to one embodiment of the present invention;
[0024] FIG. 3A shows an exploded view of an actuation mechanism for
an automatic injector, according to one embodiment of the present
invention, which resides substantially within the upper housing
when assembled;
[0025] FIG. 3B shows an enlarged view of the actuation mechanism
shown in FIG. 3A;
[0026] FIG. 3C shows a cross-sectional view of the actuation
mechanism shown in FIG. 3A;
[0027] FIG. 3D shows a 90 degree rotation of the cross-sectional
view shown in FIG. 3C;
[0028] FIG. 4 shows a cross-sectional view of a plunger of a
retractable syringe component of an automatic injector, according
to one embodiment of the present invention;
[0029] FIG. 5 shows an automatic injector including an actuation
mechanism, according to one embodiment of the present invention, in
a locked configuration;
[0030] FIG. 6A shows an automatic injector including an actuation
mechanism, according to one embodiment of the present invention, in
an injection configuration;
[0031] FIG. 6B shows an automatic injector including an actuation
mechanism, according to one embodiment of the present invention, in
a drug dosing configuration;
[0032] FIG. 7 shows an automatic injector including an actuation
mechanism, according to one embodiment of the present invention, in
a retraction activated configuration;
[0033] FIG. 8 shows an automatic injector including an actuation
mechanism, according to one embodiment of the present invention, in
a retraction completed configuration;
[0034] FIG. 9 shows an embodiment of a needle assembly engaged by a
plunger prior to retraction;
[0035] FIG. 10 shows an enlarged view of the retraction activated
configuration shown in FIG. 7, in which an embodiment of a release
ring disengages a plunger inner from a plunger outer to facilitate
spring decompression and needle retraction; and
[0036] FIG. 11 shows an enlarged view of the retraction completed
configuration shown in FIG. 8.
DETAILED DESCRIPTION
[0037] The novel devices of the present invention provide
integrated safety features which automatically retract the needle
or cannula into the device and provide true end of dose indication
to users. Such devices are safe and easy to use, and are
aesthetically and ergonomically appealing for self-administering
patients. The devices described herein incorporate features which
make activation, operation, and lock-out of the device simple for
even untrained users. The novel devices of the present invention
provide these desirable features without any of the problems
associated with known prior art devices.
[0038] As used herein to describe the actuation mechanisms,
automatic injectors, syringe cartridges, or any of the relative
positions of the components of the present invention, the terms
"axial" or "axially" refer generally to a longitudinal axis "A"
around which the actuation mechanisms and automatic injectors are
preferably positioned, although not necessarily symmetrically
there-around. The term "radial" refers generally to a direction
normal to axis A. The terms "proximal," "rear," "rearward," "back,"
or "backward" refer generally to an axial direction in the
direction "P" of the plunger. The terms "distal," "front,"
"frontward," "depressed," or "forward" refer generally to an axial
direction in the direction "D" of the needle. As used herein, the
term "glass" should be understood to include other similarly
non-reactive materials suitable for use in a pharmaceutical grade
application that would normally require glass. The term "plastic"
may include both thermoplastic and thermosetting polymers.
Thermoplastic polymers can be re-softened to their original
condition by heat; thermosetting polymers cannot. As used herein,
the term "plastic" refers primarily to moldable thermoplastic
polymers such as, for example, polyethylene and polypropylene, or
an acrylic resin, that also typically contain other ingredients
such as curatives, fillers, reinforcing agents, colorants, and/or
plasticizers, etc., and that can be formed or molded under heat and
pressure. As used herein, the term "plastic" does not include
either glass or elastomers that are approved for use in
applications where they are in direct contact with therapeutic
liquids that can interact with plastic or that can be degraded by
substituents that could otherwise enter the liquid from plastic.
The term "elastomer," "elastomeric" or "elastomeric material"
refers primarily to cross-linked thermosetting rubbery polymers
that are more easily deformable than plastics but that are approved
for use with pharmaceutical grade fluids and are not readily
susceptible to leaching or gas migration. "Fluid" refers primarily
to liquids, but can also include suspensions of solids dispersed in
liquids, and gasses dissolved in or otherwise present together
within liquids inside the fluid-containing portions of syringes.
The term "spring" is used herein with reference to one or more
"biasing members," and any type of spring or other biasing member
may be utilized within the inventions herein.
[0039] FIGS. 1A and FIG. 1B show an embodiment of automatic
injector 100 which includes upper housing 14 and lower housing 16.
Upper housing 14 and lower housing 16 may be made of any of a
number of materials including plastics and glass, but are
preferably made of plastic. Upper housing 14 and lower housing 16
may be one unified component consisting of two portions or, as
shown in FIGS. 1A and 1B, two separate components. When upper
housing 14 and lower housing 16 are two separate components they
may be fixedly connected, for example by a glue or adhesive, or
removably attached, for example by a screw-fit connection.
Automatic injector 100 may also include activation mechanism 12 and
cap 18. FIG. 1B shows the interior components of automatic injector
100, i.e., with the upper housing 14 and lower housing 16 hidden
from view. As shown in FIG. 1B, automatic injector 100 includes
activation mechanism 12, actuation mechanism 10, and syringe
cartridge 20 having a plunger 200 (shown in FIG. 4) and needle
assembly 40. Cap 18 has been removed for operation of the automatic
injector 100 shown in FIG. 1B, but would be removably attached to
automatic injector 100 at the distal end D of the device and
removed at time of use by the user. FIG. 1B shows the components of
actuation mechanism 10 and automatic injector 100, according to at
least one embodiment of the present invention, in a locked
configuration.
[0040] In at least one embodiment, the activation mechanism 12 is a
button which may, for example, be rotated to unlock the device and
depressed to activate the device, as is detailed further herein.
The activation mechanism is shown at proximal end P of automatic
injector 100. Typically, drug chamber 222 contains a liquid
substance or drug dose for delivery through the needle assembly 40
to a patient. Upon depression, i.e., axial motion in the distal
direction, activation mechanism 12 permits actuation mechanism 10
to actuate the needle injection, drug dose delivery, and retraction
activation stages of operation. Retraction activation by the
actuation mechanism 10 enables retraction of the needle assembly 40
into syringe cartridge barrel 202 and automatic injector 100, as is
detailed further herein.
[0041] FIGS. 3A-3D further detail the actuation mechanism 10,
according to at least one embodiment of the present invention,
which is a component of the automatic injector. FIG. 3A shows the
components of actuation mechanism 10 in an exploded view, in
addition to upper housing 14, while FIG. 3B shows these components
in a compressed view prior to actuation. In at least one
embodiment, actuation mechanism 10 includes first actuation spring
102, first actuation pill 104, second actuation spring 106, and
second actuation pill 108. In a compressed configuration prior to
actuation, the first actuation spring 102 rests in a compressed,
energized state substantially within an upper portion of first
actuation pill 104. In this compressed configuration, first
actuation pill 104 and second actuation pill 108 are detachably
connected, as shown in FIG. 3B, between which second actuation
spring 106 resides in a compressed, energized state. Actuation
mechanism is maintained in a compressed state by engagement between
connector prongs 104B of first actuation pill 104 and connection
bridges 108B of second actuation pill 108. The connector prongs
104B and connection bridges 108B are maintained in engagement by
interaction between protrusions 104D of first actuation pill 104
and the inner diameter of upper housing 14, as is detailed below.
Protrusions 104D may travel within longitudinal channels in the
inner diameter of the housing to maintain the rotational alignment
of the actuation mechanism. Guide prongs 104C of first actuation
pill 104 similarly interface with the inner diameter of the housing
to maintain the actuation mechanism 10 in rotational alignment
within the automatic injector.
[0042] FIGS. 3C-3D provide cross-sectional views of the actuation
mechanism 10 within upper housing 14 prior to activation or
actuation of the automatic injector. FIG. 3D shows a 90 degree
axial rotation view of the view shown in FIG. 3C. As shown, locking
hooks 104A of first actuation pill 104 initially engage locking
plateau 14B of upper housing 14. Upon activation of the automatic
injector and actuation mechanism by the activation mechanism,
locking hooks 104A are caused to move radially inwards and
disengage from locking plateau 14B. As would be appreciated by an
ordinarily skilled artisan, the term "hooks" is meant to reference
any type of engagement mechanism including, for example, prongs,
latches, tabs, and the like. Upon such disengagement, first
actuation spring 102 is permitted to expand from its compressed,
energized state, thereby axially translating first actuation pill
104 in the distal direction. First actuation pill 104 and second
actuation pill 108 are retained in engagement during this initial
axial translation due to the engagement between connector prongs
104B of first actuation pill 104 and connection bridges 108B of
second actuation pill 108 described above. Such operation of the
actuation mechanism 10 is also shown in FIGS. 5, 6A, and 6B, in
which actuation mechanism 10 is incorporated into an automatic
injector 100. As shown in FIG. 5, retention prongs 108A of second
actuation pill 108 are initially used to engage bottom of release
ring 236 to maintain the position of the syringe cartridge and
needle assembly within the housing during, for example, removal of
the needle shield. The retention prongs 108A may also be used to
brace against barrel 202 of syringe cartridge 20 to ensure
substantially axial alignment of these components during storage,
transport, and operation of the actuation mechanism and automatic
injector. Support ring 22 may similarly be utilized to ensure
substantially axial alignment of the components.
[0043] Referring now to FIGS. 5-8, expansion of the first actuation
spring 102 and the resulting axial translation of the actuation
mechanism 10 in the distal direction causes exposure of the needle
assembly 40 from the distal end of the automatic injector, such as
for injection of a needle into a user. This is evident in the
transition of components shown in FIGS. 5, 6A, and 6B. The axial
translation of the actuation mechanism in the distal direction
causes plunger 200 to also move in the distal direction, while
syringe cartridge is held substantially in place by engagement
between release ring 236 and lower housing plateaus 16A. Lower
housing plateaus 16A may also be located at various positions
within the lower housing to limit the depth of needle insertion.
Distal translation of the plunger 200 within barrel 202 of syringe
cartridge 20 forces a liquid, such as a drug treatment, from drug
chamber 222 through needle assembly 40 and into a user for drug
delivery, as is detailed further below. As such, expansion of the
first actuation spring 102 initially drives insertion of the needle
into the patient to a desired depth specified by the location of
the lower housing plateaus 16A within the housing. Upon interaction
between release ring 236 and lower housing plateaus 16A to block
further travel of the syringe cartridge, the continued expansion of
the first actuation spring 102 proceeds to translate plunger 200
within barrel 202 to deliver the drug dose.
[0044] Referring now to FIG. 4, plunger 200 comprises plunger inner
210 comprising shaft 211, aim 232, annular ledge 212 and
seal-engaging member 216, which in this embodiment is a screw
threaded projection at the distal end of plunger 200, which engages
complementary, screw-threaded recess 820 of plunger seal 800.
Plunger seal 800 further comprises needle-engaging portion 810.
Plunger 200 further comprises plunger outer 220 having elongate
body 221 with base 225 and locking member 227. Plunger 200 further
comprises plunger spring 270 which is mounted between plunger inner
210 and plunger outer 220, held in an initially compressed state
between ledge 212 of plunger inner 210 and base 225 of plunger
outer 220. Initially, ledge 235 of arm 232 abuts rim 229 of plunger
outer 220 to prevent axial movement of plunger inner 210 relative
to plunger outer 220. However, arm 232 of plunger inner 210 is
resiliently flexible and movable in the direction of the solid
arrow shown in FIG. 4, which will allow disengagement of plunger
inner 210 from plunger outer 220 to facilitate decompression of
plunger spring 270, as will be described hereinafter.
[0045] Referring now to FIG. 9, needle assembly 40 includes cannula
410, needle body 420, retainer 300, needle seal 430 and ejector
600. The needle assembly 40 is mounted into the distal end of
barrel 202 of the syringe cartridge. FIG. 9 shows the components in
the retraction activation stage, when contact between plunger seal
800 and needle seal 430, needle seal 430 and ejector 600, and
ejector 600 and arms 320A, B of retainer 300 cause hook-ends 321A,
B of retainer 300 to disengage from needle body 420 for retraction
of needle assembly 40. Cannula 410 may be a number of fluid tubes
but is preferably a rigid needle, such as a rigid steel needle.
Prior to or upon retraction activation, plunger recess 860 of
plunger seal 800 engages proximal segment 425 of needle body 420
for retraction of needle assembly 40. The retraction activation
stage is detailed further with reference to the operation of
automatic injector 100 in FIGS. 5-8 hereinafter.
[0046] Operation of actuation mechanism 10 and automatic injector
100 will be described with particular reference to FIGS. 1-3 and
5-8. In these embodiments, drug chamber 222 of barrel 202 contains
a fluid suitable for injection into a user. As evident in FIG. 5,
safety cap 18 (shown also in FIG. 1A) has been removed from lower
housing 16 to allow activation of the device, injection of the
needle assembly, and drug delivery. Initially, activation mechanism
12 is in a locked configuration enabled by the releasable
engagement between locking prongs 14A of upper housing 14 and
locking grooves 12A of activation mechanism 12. Locking grooves 12A
may be channels, detents, or the like along the radial
circumference of the activation mechanism, as shown in FIG. 1B,
within which locking prongs 14A may travel. Initially, the locking
prongs 14A are in a position within the locking grooves 12A which
prevents depression of the activation mechanism 12. The activation
mechanism 12 may be rotated around the longitudinal axis to an
unlocked position, where the locking prongs 14A are aligned with a
portion of the locking grooves 12A that permits axial depression of
the activation mechanism 12. Optionally, an activation spring 122
may be retained within the activation mechanism 12, between the
activation mechanism and the proximal end of the upper housing 14,
for example to maintain the activation mechanism 12 in a locked
position until user operation and to provide the user tactile
resistance upon activation. This provides useful user feedback to
ensure that the proper injection procedures are followed with the
device and that removal of the cap is completed prior to
injection.
[0047] In the configurations shown in FIG. 3D and FIG. 5, locking
hooks 104A of first actuation pill 104 initially engage locking
plateau 14B of upper housing 14. After removal of the cap and
unlocking of the activation mechanism, such as by axial rotation of
the activation mechanism, the device may be placed in contact with
the target location of the user and activated for injection, drug
delivery, and needle retraction. Upon activation of the automatic
injector and actuation mechanism by the activation mechanism,
locking hooks 104A are caused to move radially inwards and
disengage from locking plateau 14B. Upon such disengagement, first
actuation spring 102 is permitted to expand from its compressed,
energized state, thereby axially translating first actuation pill
104 in the distal direction. First actuation pill 104 and second
actuation pill 108 are retained in engagement during this initial
axial translation due to the engagement between connector prongs
104B of first actuation pill 104 and connection bridges 108B of
second actuation pill 108 described above. This stage initiates
needle insertion into the patient and begins drug delivery to the
patient.
[0048] FIGS. 6A and 6B show the automatic injector, in a
cross-sectional view that is 90 degrees rotated around the axis
from the view shown in FIG. 5, after the device has been activated.
As the first actuation spring 102 continues to expand from its
compressed, energized state, it causes axial translation of the
actuation mechanism in the distal direction. This action of the
actuation mechanism forces plunger 200 to also move in the distal
direction (in the direction shown by the hatched arrow), while
syringe cartridge 20 is held substantially in place by engagement
between release ring 236 and lower housing plateaus 16A. Lower
housing plateaus 16A may also be located at various positions
within the lower housing to limit the depth of needle insertion.
Distal translation of the plunger 200 within barrel 202 of syringe
cartridge 20 forces a liquid, such as a drug treatment, from drug
chamber 222 through needle assembly 40 and into a user for drug
delivery. The dimensions of the components and the lengths of axial
travel within the device are configured such that protrusions 104D
of first actuation pill 104 reach interior recesses 16D of lower
housing 16 just prior to, or substantially at the same time as,
plunger seal 800 contacting the needle seal of needle assembly 40,
effectively ensuring that the recess of needle seal 800 has
engagedly captured segment 425 of the needle body of the needle
assembly 40 for retraction and prior to activation of the
retraction mechanism. Alternatively, interior recesses may be
dimensioned and located at various points in the upper housing, or
within a unified housing body, yet function in the same manner as
described in the embodiment shown in FIGS. 6A and 6B. Similarly,
interior recesses may be changes in inner diameter between the
upper and lower housings. At this stage, protrusions 104D of first
actuation pill 104 are permitted to spring radially outwards into
interior recesses 16D of lower housing 16 (in the directions shown
by the solid arrows in FIG. 3B). This action enables connector
prongs 104B of first actuation pill 104 to disengage from
connection bridges 108B of second actuation pill 108, thereby
actuating the function of the second actuation pill.
[0049] FIG. 7 shows the automatic injector, in the same
cross-sectional viewing angle as FIG. 5, as the second actuation
pill is actuated. As described above, upon release of the connector
prongs 104B of first actuation pill 104 from their engagement with
connection bridges 108B of second actuation pill 108, second
actuation spring 106 is permitted to expand from its compressed,
energized state, thereby driving the plunger further in the distal
direction. Second actuation spring 106 is prevented from driving
the first actuation pill in the proximal direction by surface
interaction between guide prongs 104C of the first actuation pill
and lockout notches 14C of upper housing 14. This configuration
ensures that substantially all of the energy stored in the second
actuation spring 106 is released in the distal direction. The
second actuation pill 108 functions to ensure that all of the drug
treatment is delivered to the user and to activate the needle
retraction mechanism.
[0050] In at least one embodiment of the present invention, the
needle retraction is essentially similar to that described in
WO2011/075760, and will be briefly described as follows with
reference to FIGS. 7-11. During delivery of fluid contents, plunger
200 moves axially through barrel 202 in the direction of the
hatched arrow in FIG. 7. As shown in FIG. 9, plunger seal 800 bears
against needle seal 430, which in turn bears against ejector 600.
Further to this, ejector ring 610 moves hook-ends 321A, B of arms
320A, B of retainer 300 radially outwardly in the direction of the
solid arrows in FIG. 9, thereby disengaging needle body 420 from
retainer 300 to release needle body 420 and cannula 410 for
subsequent retraction. At this point, recessed seat 810 of plunger
seal 800 has engaged segment 425 of retractable needle body 420 and
recess 860 has received fluid end 412 of cannula 410. This
effectively couples needle body 420 and cannula 410 to plunger
inner 210 since plunger inner 210 is connected to the proximal end
of plunger seal 800.
[0051] As shown in FIG. 7 and FIG. 10, in order for needle body 420
and cannula 410 to retract at the end of delivery of fluid
contents, compressed spring 270 must decompress, which is
facilitated by plunger inner 210 disengaging from plunger outer
220. This disengagement is facilitated by release ring 236. As
plunger inner 210 and plunger outer 220 are substantially fully
depressed (i.e., axially translated in the distal direction as per
the hatched arrow) to inject fluid from barrel 202, one or both may
contact release ring 236. Through this contact, release ring 236
moves arm 232 radially inwardly (in the direction of the solid
arrow) and out of engagement with rim 229 of plunger outer 220.
This disengagement allows compressed spring 270 to decompress and
push against ledge 212 (shown in FIG. 4 and FIG. 7) of plunger
inner 210 to thereby retract plunger inner 210 with plunger seal
800, needle body 420, and cannula 410 coupled thereto. Plunger
outer 220 remains substantially in contact or connection with
release ring 236, while plunger inner 210 coupled to needle body
420 and cannula 410 is axially translated in the proximal direction
by decompression of spring 270, thereby retracting cannula 410 and
needle body 420. FIG. 8 and FIG. 11 show the components of the
automatic injector after needle retraction has completed. At this
stage, cannula 410 is fully retracted into the housing and/or
barrel 202. This needle or cannula retraction is highly desirable
as it provides integrated safety features while simultaneously
providing a true end of dose indication to the user.
[0052] Suitably, automatic injector 100 provides one or more
locking systems for plunger 200. As shown in FIGS. 7, 8, and 11, in
one embodiment of said locking system, plunger outer 220 of plunger
200 includes locking member 227 having edge 228 which engages
underside 237 of release ring 236 after needle retraction. This
engagement prevents or impedes further movement of plunger 200
relative to the release ring 236 in the proximal direction, as
shown in FIG. 11, while plunger inner 210 is permitted to move in
the proximal direction. Accordingly, in addition to initially
assisting in the activation of needle retraction, the release ring
236 may secondarily function to lock plunger 200 after initial use
to thereby prevent re-use. As stated above, the force of the second
actuation spring acting upon the plunger outer itself may
additionally or alternatively prevent or "lock-out" the plunger
outer from axial travel in the proximal direction after
actuation.
[0053] Certain optional standard components or variations of
automatic injector 100 are contemplated while remaining within the
breadth and scope of the present invention.
[0054] For example, upper or lower housings may optionally contain
one or more transparent or translucent windows 50, as shown in FIG.
1, to enable the user to view the operation of the automatic
injector or verify that drug dose has completed. Additionally, an
optional needle shield 52 may be utilized, as shown in FIG. 5, to
protect cannula 410. The needle shield 52 may be connected, for
example, to cap 18 and removed prior to operation of the automatic
injector 100. Similarly, one or more of the components of actuation
mechanism 10 and automatic injector 100 may be modified while
remaining functionally within the breadth and scope of the present
invention. For example, as described above, while the housing of
automatic injector 100 is shown as two separate components upper
housing 14 and lower housing 16, these components may be a single
unified component. Similarly, while support ring 22 is shown as a
separate bracing component, it may be a pre-formed aspect on the
inner diameter of the housing. Such standard components and
functional variations would be appreciated by one having ordinary
skill in the art and are, accordingly, within the breadth and scope
of the present invention. It will be appreciated from the foregoing
that the actuation mechanisms and automatic injectors disclosed
herein provide an efficient and easily-operated system for
automated drug delivery from a drug container, with integrated
safety features and true end of dose indication to the user.
[0055] Assembly and/or manufacturing of actuation mechanism 10,
automatic injector 100, or any of the individual components may
utilize a number of known materials and methodologies in the art.
For example, a number of known cleaning fluids such as isopropyl
alcohol and hexane may be used to clean the components and/or the
devices. A number of known adhesives or glues may similarly be
employed in the manufacturing process. Additionally, known
siliconization fluids and processes may be employed during the
manufacture of the novel components and devices. Furthermore, known
sterilization processes may be employed at one or more of the
manufacturing or assembly stages to ensure the sterility of the
final product.
[0056] The automatic injector may be assembled in a number of
methodologies. In one method, the second actuation spring is first
compressed between a first actuation pill and a second actuation
pill. The second actuation spring may be locked in a compressed,
energized state by detachably engaging one or more connector prongs
of the first actuation pill with one or more respective connection
bridges of second actuation pill. A first actuation spring may
subsequently be inserted into a housing and compressed between the
housing and the first actuation pill by detachably engaging one or
more locking hooks of the first actuation pill with a locking
plateau of the housing. In this configuration, wherein the first
actuation spring is initially maintained in a compressed, energized
state substantially within an upper portion of the first actuation
pill. A syringe cartridge comprising a plunger and a needle
assembly may be inserted into the housing such that a proximal end
of the plunger contacts the second actuation pill. Alternatively,
the syringe cartridge, or components thereof including the plunger,
may be connected to the second actuation pill prior to insertion of
the components into the housing. For example, the proximal end of
the plunger outer may interface with one or more engagement
features within the second actuation pill. This enables, for
example, rotational alignment of the plunger, prevents shifting of
the plunger from a substantially axial alignment, and helps ensure
an even distribution of force onto the plunger upon actuation of
the first and second actuation pills. The syringe cartridge may be
a number of syringes such as, for example, a prefilled syringe
containing a drug treatment. Preferably, the syringe is a prefilled
retractable syringe, as described above. The method may further
include the step of: attaching an activation mechanism to the
housing, wherein the activation mechanism is configured to contact
the one or more locking hooks of the first actuation pill upon
activation. The activation mechanism may be positioned such that it
is in a locked configuration for, for example, shipping and storage
of the automatic injector. Additionally, the method may include the
step of attaching a cap having a needle shield aspect, or attaching
separate cap and needle shield, to the distal end of the syringe
cartridge and automatic injector. When the cap and needle shield
are separate components, the support ring may be utilized to brace
the proximal end of the needle shield during attachment of the cap.
This also helps to prevent pressurization of the syringe cartridge
during assembly.
[0057] As discussed above, a glue or adhesive may be utilized to
affix one or more components of the actuation mechanism and/or
automatic injector to each other. Alternatively, one or more
components of the actuation mechanism and/or automatic injector may
be a unified component. For example, the upper housing and lower
housing may be separate components affixed together by a glue or
adhesive, a screw fit connection, an interference fit, and the
like; or the upper housing and lower housing may be a single
unified component. These components may be sterilized individually
or together, and may be assembled in a sterile environment or
sterilized after assembly. Similarly, the assembly of the
embodiments of the present invention may utilize a number of other
standard manufacturing practices.
[0058] The automatic injector may be utilized in a number of
different ways. For example, in one embodiment the method of
operating an automatic injector includes the step of: (i)
disengaging one or more locking hooks of a first actuation pill
from a locking plateau of a housing, wherein such disengagement
permits a first actuation spring to expand substantially along a
longitudinal axis of the housing from its initial energized state.
The expansion of the first actuation spring translates the
actuation mechanism substantially along an axis of the automatic
injector in the distal direction. As the first actuation pill
reaches one or more recesses in the inner surface of the housing,
the first actuation pill is permitted to disengage from the second
actuation pill. In a preferred embodiment, this disengagement
occurs when one or more connector prongs of the first actuation
pill disconnect from corresponding connection bridges of the second
actuation pill. This disconnection permits a second actuation
spring to expand substantially along the longitudinal axis of the
housing from its initial energized state.
[0059] Protrusions on the connector prongs of the first actuation
pill may be utilized to bias the connector prongs into engagement
with the connection bridges when in the connected stage. Such
protrusions may be permitted to expand into the recesses of the
inner surface of housing as the actuation mechanism reaches the
recesses, thereby permitting disconnection between the one or more
connector prongs of the first actuation pill and the corresponding
connection bridges of the second actuation pill. The actuation
mechanism may initially drive the needle injection and drug
delivery into the patient. Subsequently, the actuation mechanism
may activate the retraction mechanism of the syringe cartridge, as
described above. The method may further include the steps of:
operating the plunger of the automatic injector to deliver a
substance to a recipient. Prior to step (i), the method may further
include the step of: unlocking an activation mechanism and
activating the activation mechanism, as described above.
[0060] Throughout the specification, the aim has been to describe
the preferred embodiments of the invention without limiting the
invention to any one embodiment or specific collection of features.
Various changes and modifications may be made to the embodiments
described and illustrated without departing from the present
invention.
[0061] The disclosure of each patent and scientific document,
computer program and algorithm referred to in this specification is
incorporated by reference in its entirety.
* * * * *